This invention relates to a valve for a pressurized package commonly referred to as an aerosol package.
Aerosol packages usually comprise a valve unit situated in the neck of the container which is opened by finger pressure against an actuator disposed at one terminus of a valve stem. The valve unit has a movable valve body and associated hollow valve stem which unseats from a gasket, thereby permitting flow of product into a hollow valve stem (product conduit).
With certain products, e.g. paints, it is desirable that the valve stem be separable from the valve body in order to clean the product conduit should drying and resultant clogging occur. To provide the aforementioned valve stem removal capability, the valve stem, at one end, is molded integral to the valve actuator to thereby permit its separation from the valve body by pulling on the actuator. At the other end the valve stem mates with a movable valve body situated beneath a resilient gasket, the valve stem being passed through a central opening in the resilient gasket. The gasket seals the product discharge orifice in the valve stem when the valve is in a closed position. By depressing the valve stem, the product orifice in the stem is open to flow of product from the container.
More particularly, the aforedescribed aerosol valve comprises a container closure, commonly called a mounting cup, which is clinched to the container bead. Within and crimped to an upstanding central portion of the mounting cup, commonly called a pedestal, is a valve housing having a resilient gasket disposed atop thereof, which gasket forms a seal between the valve housing and the mounting cup. Disposed within the housing is reciprocable valve closing/opening member comprising a valve body and valve stem, which body and stem have communicating passages for egress of the pressurized product to a discharge orifice situated in a finger depressible actuator.
The aerosol valve described above is commonly referred to in the aerosol industry as a "female" valve, in contrast to the so called "male" valve wherein the valve stem is molded integral to the valve body. U.S. Pat. Nos. 3,033,473, 3,061 203, 3,074,601 and 3,209,960 describe aerosol valves of the "female" type and U.S. Pat. No. 2,631,814 and aerosol valve of the "male" type.
Furthermore, in prior or aerosol valves, the product orifice in the valve stem is formed by a radial pin extending laterally through the wall of the valve stem, a so-called "side action" molding operation. The presence of the "side action" pin necessitates the removal of the pin before ejection of the molded part, with a consequent time delay in the molding operation. Moreover, with orifice sizes commonly used in aerosol valves the "side action" pin often breaks with consequent shutdown of the molding operation.
Additionally, in prior aerosol valves, the central opening of the gasket seals radially against the product orifice in the valve stem. This sealing of the valve stem orifice upon closure of the valve forecloses gravitational return of the product in the hollow valve stem from moving past the valve stem orifice with the often consequent result that residual product in the hollow valve stem drys and clogs the passage in the valve stem.
It is an objective of this invention to provide an aerosol valve that obviates the aforementioned disadvantages of prior art valves.